[old_master]

Is the Service Engine Soon light on? If so, what are the codes?

Ignition timing: Under the dash, on the passenger side, behind the carpet, taped to the firewall, is a single tan wire with a black connector. Unplug the connector and check/adjust the ignition timing. After it's adjusted properly, plug the connector back together.


Runs poor after a few minutes: When the engine is first started, the ECM controls the engine in what is called "open loop" operation. During this time it ignores the oxygen sensor voltage and uses a pre-determined air/fuel mixture and base ignition timing. After the engine warms up, the ECM goes into what is called "closed loop" operation and begins watching the oxygen sensors and adjusting air/fuel mixture and ignition timing.

Bring the engine to operating temperature, check/adjust ignition timing, then bring idle speed to approximately 1500 RPM and check oxygen sensor voltage at the sensor(s). It should fluctuate roughly between .2VDC and .9VDC. Post your results.